The evolution of the interventional treatment of erectile dysfunction has a colorful history. Initial attempts centered around external splints. Overlapping efforts then included trusses and external constriction about the root of the male organ and vacuum devices designed to fill the organ passively combined with a circular constrictor, again placed at the root of the male organ.
Surgically implantable sphincter systems with inflatable constrictors placed at the root of the organ or each arm of the cavernosa have also been offered. Additional ideas included implantable rigid rods and malleable rods. Commensurate with these, various hydraulically activated fully implantable devices requiring multiple insertion sites show a multiplicity of designs. Many associated devices and related implements have also been presented to support such systems.
One known type of penile implant device, for example, includes a pair of cylindrical prostheses that are implanted into the corpus cavernosae of the penis. The prostheses are inflatable and are connected to a fluid-filled reservoir through a pump and valve assembly. Such a pump assembly is typically implanted into the scrotum of the patient, and the reservoir is implanted in the abdomen. To activate the penile implant device, the patient actuates the pump using one of a variety of methods that cause fluid to be transferred from the reservoir through the pump and into the prostheses. This results in the inflation of the prostheses and produces rigidity for an erection. Then, when the patient desires to deflate the prostheses, a valve assembly within the pump is actuated in a manner such that the fluid in the prostheses is released back into the reservoir. This deflation returns the penis to a flaccid state.
The surgical approach to erectile dysfunction has inherent risks including the erosion of the tissues surrounding the devices when constant pressure due to the rigidity of the device is applied to these tissues. A second risk is that of infection, a great deal of which is related to handling of the scrotal tissues required for the remote implantation of devices, the scrotum being in close proximity to the perineal structures and anal region which is difficult to sanitize for surgical procedures. Placement of a remote reservoir within the pre-peritoneal and/or the intra-abdominal cavities carries the risks of intra-abdominal infection, bowel erosion or obstruction, adhesive compression of the reservoir and all connections are at risk of leak or disconnection. In addition, the routing of tubing from element to element is also a source of long term discomfort to the user.
Any surgical implantation will include the risk of intra-operative or post-operative bleeding. Elimination of multiple surgical sites can reduce this risk substantially, the skill and technique of the implanting surgeon being the final, but uncontrollable factor. The limiting factor of hydraulic implants has been the amount of fluid required to initiate a substantial erection and the storage of that fluid when the erectile unit is decompressed. This required volume, heretofore, has required a rather voluminous reservoir.
More recently, unitized devices have been proposed which contain the necessary elements to initiate an erection without the necessity of implantation of remote reservoirs or inflation pumps and the associated tubing required to connect these elements. While these devices may reduce many of the surgical risks described above, because of their design, there is insufficient fluid volume to allow the implant to operate properly.
Therefore, a need exists for a unitized implantable erectile device that requires a much reduced volume of fluid that can be stored within the unitized device without significantly restricting the final length of the erect implant.